if the economy response, they will continue the policy rate for a long time. another man who knows a thing or two about the economy, a man who actually ran the fed -- we're talking about alan greenspan. he coined the term rational exubera and. -- rational exuberance. he has just written a book about bubbles. that is not his concern. >> i am more concerned about the fundamentals. >> of the overall economy? >> exactly. then i am about the state of euphoria. what iso you say that? the red light on your radar that you are concerned about? >> first of all, profits have been rising. is, a share of national income has been rising to levels which cannot persist. slowdown inven a the rate of increase in the share of profits, that in and of itself slows the growth in earning and eventually slows the expectations for future earnings. that is one. the main issue is interest rates. i have written in the book that i published two weeks ago -- it is very difficult for me to see that we are not on the edge of a significant rise in long-term rates. i do not know when that is.